Unencrypted DNS queries can be intercepted by third parties, revealing your browsing habits. Android does offer DNS encryption but it's not much configurable. But this should not prevent us from protecting our privacy.
Fyrypt - a firewall app - solves this by using dnscrypt-proxy to encrypt your DNS traffic, protecting your browsing data from being monitored by external parties. And there's no complicated configuration or setup. Just enable the service in the app. And you are protected.
If you are a tech-savvy, there's a long list of configurable options. Among others, you can allow and block a domain list of your choice.
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